| 摘要 |
PROBLEM TO BE SOLVED: To increase an S/N ratio so as to improve knocking detecting accuracy by setting a knocking judging level a value eliminated mechanical vibration noise component and electric noise component from a detected result of knocking detecting means at the time of non-knocking, and judging knocking on the basis of the knocking judging level. SOLUTION: In the case where knocking is detected by an ECU 40, since a peak value of an output signal of a knocking sensor 18 and a back ground level include mechanical vibration noise component NK and electric noise component Nd on the basis of driving of an electric load, those noise components Nk and Nd are eliminated from the peak value of the output signal of the knocking sensor 18 by the CPU, and only vibration component by combustion is taken out. An adapted constant K is multiplied by a value eliminated the noise components Nk, Nd from the back ground level, and a knocking judging level is found out. It is compared whether the vibration component by combustion is larger than the knocking judging level or not, and it is judged whether knocking of an engine 11 is generated or not. |
